A conventional disk harrow assembly includes a draft frame mounted for rolling movement over a field and including an elongated beam. An elongated shaft having a plurality of earth working disks mounted for rotation therewith is rotatably supported by bearing standards to and beneath the beam. Each bearing standard includes a bearing for rotatably accommodating a lengthwise portion of the elongated shaft.
Some fields have stones, rocks, stumps, and/or other obstacles at or near the top surface of the field. Such obstacles cause impact loads to be applied to the bearings and disks. Therefore, it is desirable to provide a resilient mounting to cushion or reduce impact loads being imparted to the bearings and disks as the disk harrow assembly passes over such obstacles during a tilling operation.
One or more generally C-shaped springs have been used in the past to cushion impact loading of the bearings and disks. Such heretofore known springs have an upper leg portion which is secured to the elongated beam on the frame and a lower leg portion having the bearing mounted at a distal end thereof. The lower leg portion is joined to the upper leg portion by a curved center portion. Moreover, the lower leg portion extends generally parallel to the upper leg portion. The bearing, therefore, deflects generally perpendicular to the second leg portion along a generally vertical or straight up path as the disks pass over stones or other forms of obstacles as the implement is drawn across a field. With heretofore known bearing standard designs, the bearing is mounted such that it is allowed to misalign only about a generally horizontal axis.
Recent research has shown that as the disks pass over an obstacle in the field, the disk tend to deflect both rearwardly and upwardly rather than straight up and down. The bearings on heretofore known bearing standards, however, are not allowed to deflect or misalign in response to both rearward and upward forces being applied thereto. Accordingly, the angularly directed impact load applied against the bearing tends to cause the bearing to bind or seize thus reducing its life expectancy. As will be appreciated, bearing failure is a problem which seriously impedes operation of the implement. Moreover, replacement of a worn or seized bearing is a time consuming and tedious process requiring extensive manual labor because of the number of individual parts comprising the disk harrow assembly.
Thus, there is a need and a desire for a disk harrow assembly including bearing standards for resiliently mounting a gang of disk harrows on a draft frame and such that impact loading caused through deflection of the disk harrows can be absorbed thus prolonging the useful life of the bearings and disks and thereby reducing costly downtime and repairs.